KR20040017846A - Multiport polishing fluid delivery system - Google Patents

Abstract

Methods and systems are provided for delivering a polishing fluid to a chemical mechanical polishing surface 104. In one embodiment, the system includes an arm 104 having a delivery portion at least partially disposed on a polishing surface. The first nozzle and the second nozzle are disposed on the delivery of the arm. The first nozzle 132 is configured to flow the polishing fluid at a first speed and the second nozzle is configured to flow the polishing fluid at a second speed that is different from the first speed. Methods of delivering a polishing fluid to a chemical mechanical polishing surface generally include supplying the polishing fluid to the semiconductor polishing surface at one location at a first speed and supplying the polishing fluid at a second speed that is different from the first speed at the second location. Supplying to.

Description

MULTIPORT POLISHING FLUID DELIVERY SYSTEM

In semiconductor wafer processing, chemical mechanical planarization, or CMP, has been preferred for its improved performance in increasing device density on substrates or semiconductor workpieces such as wafers. Chemical mechanical planarization systems generally utilize a polishing head to hold and press the substrate against the polishing surface of the polishing material while providing movement between the substrate and the polishing surface of the polishing material. Certain planarization systems utilize a polishing head that is movable on a stationary platen that supports the polishing material. Other systems use different configurations to provide relative movement between the polishing material and the substrate, for example to provide a rotating platen. The polishing fluid is generally placed between the substrate and the polishing material during polishing to provide chemical activity to aid in the removal of material from the substrate. Certain polishing fluids may also contain an abrasive.

One challenge in developing robust polishing systems and methods is to provide uniform material removal across the polished surface of the substrate. For example, as the substrate moves across the polishing surface, the edges of the substrate are often polished at higher speeds. This is partly due to the "nose drive" tendency of the substrate due to the frictional force as the substrate moves across the polishing surface.

Another problem that affects the polishing uniformity across the surface of the substrate is that certain materials tend to be removed faster than the surrounding materials. For example, copper is generally removed more quickly than materials surrounding the copper material (generally oxides) during polishing. Faster removal of copper, often referred to as dishing, is particularly evident when the width of the copper surface exceeds 5 microns.

Many solutions have been used to mitigate substrate non-uniformity as a result of polishing, but none have been completely satisfactory. Therefore, the need for a uniform, more planarized surface is still a top concern due to the trend towards reduced line size and increased device density.

Therefore, there is a need to improve polishing uniformity in chemical mechanical planarization systems.

Embodiments of the present invention generally relate to a method and apparatus for polishing a substrate in a chemical mechanical polishing system.

BRIEF DESCRIPTION OF THE DRAWINGS A more detailed description of the invention briefly summarized, with reference to the embodiments shown in the accompanying drawings, will achieve and explain in more detail the above-described features of the invention. It should be noted, however, that the appended drawings illustrate only general embodiments of the invention and are not intended to limit the scope of the invention, but may be applied to other equally effective embodiments of the invention.

1 is a simplified schematic diagram of a polishing system with one embodiment of a polishing fluid delivery system.

2 is a plan view of the system of FIG.

3 is a simplified schematic diagram of another polishing fluid delivery system.

4 is a comparison of polishing uniformity on a substrate polished in the conventional polishing system and the system of FIG.

5 is a plan view of another embodiment of a polishing fluid delivery device.

6 is a cross-sectional view of the polishing fluid delivery device taken along line 6-6 of FIG.

7 is a partial top isometric view of one embodiment of a collet for maintaining a polishing fluid delivery tube in a polishing fluid delivery device.

8 is a partial cross-sectional view of the polishing fluid delivery device taken along line 8-8 of FIG.

9 is a cutaway isometric view of another embodiment of a polishing fluid delivery device.

In order to facilitate understanding, the same reference numerals are used for the same members that are common in the drawings.

In one aspect of the invention, a system for delivering a polishing fluid to a chemical mechanical polishing surface is provided. In one embodiment, the system includes an arm having a delivery portion at least partially disposed on the polishing surface. The first nozzle and the second nozzle are disposed on the delivery of the arm. The first nozzle is configured to flow the polishing fluid at a first speed and the second nozzle is configured to flow the polishing fluid at a second speed that is different from the first speed.

In another aspect of the invention, a method of delivering a polishing fluid to a chemical mechanical polishing surface is provided. In one embodiment, the method includes supplying a polishing fluid to a first location of the chemical mechanical polishing surface at a first speed and providing the polishing fluid to a second location of the polishing surface at a second speed that is different from the first speed. It includes.

1 illustrates one embodiment of a polishing system 100 for polishing a substrate 112 with a polishing fluid delivery system 102 that controls the distribution of polishing fluid 114 across the polishing material 108. do. Examples of polishing systems that may be advantageously configured from aspects of the present invention are disclosed in US Patent Application No. 09 / 144,456 and Tolles et al., Filed Feb. 4, 1999 by Birang et al. US Pat. No. 5,738,574, issued April 14, 2014, all of which are incorporated herein by reference in their entirety. Although the polishing fluid delivery system 102 is disclosed with reference to the polishing system 100 shown, the present invention also finds use in other polishing systems for treating a substrate in the presence of a polishing fluid.

In general, the exemplary polishing system 100 includes a platen 104 and a polishing head 106. The platen 104 is generally located under the polishing head 106 that holds the substrate 112 during polishing. The platen 104 is generally disposed on the base 122 of the system 100 and coupled to a motor (not shown). The motor rotates the platen 104 to provide at least some relative polishing movement between the substrate 112 and the polishing material 108 over the platen 104. It is understood that relative motion between the substrate 112 and the polishing material 108 may be provided in other ways. For example, at least some of the relative motion between the substrate 112 and the polishing material 108 moves the polishing head 106 on the stationary platen 104 and moves the polishing material linearly below the substrate 112. And moving both the polishing material 108 and the polishing head 106, and the like.

The polishing material 108 is generally supported by the platen 104 such that the polishing surface 116 faces up towards the polishing head 106. Generally, the polishing material 108 is secured to the platen 104 by adhesive, vacuum, mechanical clamping, or the like during processing. Optionally, and especially in applications where the polishing material 108 is configured as a web, the polishing material 108 may be coated with the polishing material 108 and platen (as disclosed in US Patent Application No. 09 / 144,456). By generally using the vacuum between the 104, it is releasably fixed to the platen 104.

The polishing material 108 may be conventional or fixed abrasive material. Conventional polishing material 108 is generally composed of foamed polymer and disposed on platen 104 as a pad. In one embodiment, conventional polishing material 108 is foam polyurethane. Such conventional polishing material 108 is available from Rodel Corporation, Newark Delaware.

The fixed abrasive polishing material 108 generally consists of a plurality of abrasive particles suspended in a resin binder disposed in a separate element on the backing sheet. The fixed abrasive polishing material 108 may be used in the form of a pad or web. When abrasive particles are contained within the polishing material itself, systems using a fixed abrasive polishing material generally use a polishing fluid that does not contain abrasive. Examples of fixed abrasive polishing materials are US Pat. No. 5,692,950, issued December 2, 1997 to Rutherford et al., And US Pat. No. 5,453,312, issued 26 September 1995 to Haas et al. Which are all incorporated herein by reference. This fixed abrasive material 108 is also available from the Minnesota Manufacturing and Mining Company (3M) company located in St. Paul, Minnesota.

The polishing head 106 is generally supported above the platen 104. The polishing head 106 maintains the substrate 120 in the recess 120 facing the polishing surface 116. The polishing head 106 generally moves toward the platen 104 during processing and presses the substrate 112 against the polishing material 108. The polishing head 106 may be stationary or rotated, isolated, orbital, linearly moved, or combined moving, while pressing the substrate 112 against the polishing material 108. One example of a polishing head 106 that may be advantageously constructed from the present invention is disclosed in US Pat. No. 6,183,354 B1, issued February 5, 2001 to Zuniga et al., Which is incorporated herein by reference. Another example of a polishing head 106 that may be advantageously constructed from the present invention is a TITAN HEAD® wafer carrier available from Applied Materials, Inc. of Santa Clara, California.

The polishing fluid delivery system 102 generally includes a delivery arm 130, a plurality of nozzles 132 disposed on the arm 130, and one or more polishing fluid sources 134. The transfer arm 130 is configured to control the distribution of the polishing fluid 114 on the polishing surface 116 of the polishing material 108. In one embodiment, the delivery arm 130 is configured to meter the polishing fluid 114 at different flow rates along the arm 130. When the polishing fluid 114 is generally supplied from a single source, the polishing fluid 114 is placed at a uniform concentration on the polishing material 108 but in varying amounts along the width (or diameter) of the polishing material 108. .

Delivery arm 130 is generally coupled to base 122 proximate to platen 104. The transfer arm 130 generally has at least a portion 136 suspended on the polishing material 108. Delivery arm 130 may be coupled to another portion of system 100 as long as portion 136 may be positioned to deliver polishing fluid 114 to polishing surface 116.

The plurality of nozzles 132 are disposed along the portion 136 of the delivery arm 130 disposed above the platen 104. In one embodiment, the nozzle 132 includes at least a first nozzle 140 and a second nozzle 142. In general, the first nozzle 140 is located inside the second nozzle 142 radially relative to the center of rotation of the polishing material 108 on the arm 130. Dispensing of the polishing fluid 114 across the polishing material 108 is controlled by flowing the polishing fluid 114 from the first nozzle 140 at a different speed than the flow from the second nozzle 142.

As shown in FIG. 2, the first nozzle 140 generally flows the polishing fluid 114 to the first portion 202 of the polishing surface 116 at a first speed and the second nozzle 142 is polished. Fluid 114 flows to the second portion 204 of the polishing surface 116 at a second rate. In this way, the distribution of the polishing fluid 114 is adjusted across the width of the polishing material 108.

Referring back to FIG. 1, the flow rates flowing out of the first and second nozzles 140, 142 are generally different from each other. Flow rates may be fixed or controllable relative to one another. In one embodiment, the fluid delivery arm 130 includes a polishing fluid supply line 124 teeed between the first and second nozzles 140, 142. Tee fitting 126 has a second delivery line 146 coupled to supply line 124 and branching from a first delivery line 144 and a first delivery line, wherein the first and second delivery Lines 144 and 146 are coupled to nozzles 140 and 142, respectively.

One or more nozzles 132 include flow control mechanism 150. Flow control mechanism 150 may be a device that provides a fixed flow rate between nozzles 140 and 142 or flow control mechanism 150 may be adjustable to provide dynamic control of flow rate. Examples of flow control mechanism 150 include fixed orifices, pinch valves, proportional valves, restrictors, needle valves, restrictors, metering pumps, mass flow controllers, and the like. Alternatively, the flow control mechanism 150 may be provided by the difference in relative pressure drop between the fluid delivery lines 144 and 146 that engage the respective nozzles 140 and 142 and the tee fitting 126.

The polishing fluid source 134 is generally disposed outside the system 100. In one embodiment, the polishing fluid source 134 generally includes a reservoir 152 and a pump 154. The pump 152 generally pumps the polishing fluid 114 from the reservoir 152 through the supply line 124 to the nozzle 132.

The polishing fluid 114 contained in the reservoir 152 is generally deionized water with chemical additives that provide chemical activity to aid in the removal of material from the surface of the substrate 112 being polished. When the polishing fluid 114 is supplied from the single source (ie reservoir 152) to the nozzle 132, the fluid 114 flowing from the nozzle 132 is substantially homogeneous, i.e., chemical reactant or entrained. The concentration of the polished abrasive does not change. Optionally, the polishing fluid may include an abrasive to aid in mechanical removal of the material from the surface of the substrate. Polishing fluids typically include Cabot Corporation of Aurora, Illinois, Rodel Inc. of Newark, Delaware, Hitachi Chemical Company of Japan, and Dupont Corporation of Wilmington, Delaware. Available from numerous companies such as Dupont Corporation).

In operation, the substrate 112 is brought into contact with the polishing material 108 located in the polishing head 106 and supported by the rotating platen 104. The polishing head 106 may move or rotate the substrate to hold the substrate stationary or to increase the relative movement between the polishing material 108 and the substrate 112. The polishing fluid delivery system 102 flows the polishing fluid 114 through the supply line 124 to the first and second polishing nozzles 140, 142.

2 shows a top view of a system 100 showing the flow of polishing fluid 114 on portions 202 and 204 of polishing material 108. The first flow 206 of the polishing fluid 114 flows from the first nozzle 140 on the first portion 202 at a first speed and the second flow 208 of the polishing fluid 114 is the second nozzle. Flow from 142 on second portion 204 at a second speed. In general, the first flow 206 is different from the second flow 208 to provide a controlled distribution of the polishing fluid 114 across the polishing surface 116 of the polishing material 208. In one embodiment, the first flow 206 has a speed that is at least about 1.15 times the speed of the second flow 208. Controlled distribution of polishing fluid 114 across polishing material 108 allows material removal from the surface of substrate 112 to control relative flow of polishing fluid 114 on polishing material 108. Is adjusted across the width. For example, referring to FIG. 2, more polishing fluid 114 may be provided to the first portion 202 of the polishing material 108 than the second portion 204. (Or vice versa) Optionally, Additional nozzles may be used to provide different amounts of polishing fluid 114 on other portions of polishing material 108, where two or more portions of polishing material 108 are at different flow rates. Has

For example, in one mode of operation, the substrate 112 polished by the system 100 is treated with a polishing fluid 114 provided from the first nozzle 140 and the second nozzle 142. The polishing fluid 114 lies on the polishing material 108 at a first speed from the first nozzle 140. The polishing fluid 114 simultaneously lies on the polishing material 108 at a second speed from the second nozzle 142. In one embodiment, the first flow rate is from about 1.2 times to about 20.0 times the second flow rate. The final polishing uniformity 402 from the process using the polishing fluid delivery system 102 is shown in FIG. 4. The uniformity 404 of conventional substrate polishing achieved using conventional polishing fluid delivery systems having the same total polishing fluid flow (i.e., the system where the polishing fluid is delivered from the single nozzle or tube to the polishing material) is compared. Is provided for. As shown in FIG. 4, uniformity 402 is improved over conventional results 404.

In a configuration with dynamic (ie adjustable) control mechanism 150, such as a proportional valve, needle valve, mass flow controller, metering pump, peristaltic pump, etc., the distribution of polishing fluid 114 on the polishing material 108 is a process. It can also be adjusted. For example, the velocity of the polishing fluid from the first nozzle 140 may be applied to the polishing material 108 at a first velocity during one portion of the process and may be adjusted to a second velocity during another portion of the process. The transfer rate of the polishing fluid 114 from the second nozzle 142 may also vary during the polishing process. It should be noted that the regulation of polishing fluid flow from the nozzles 140, 142 is infinite. The use of additional nozzles disposed between the first nozzle 140 and the second nozzle 142 results in more or less polishing fluid in the nozzles where the uniformity profile is disposed between the first nozzle 140 and the second nozzle 142. By providing 114 it may also be modified and locally formed (see the description of FIG. 3 below).

Optionally, the polishing fluid delivery system with dynamic control of the flow rate from the nozzles 140, 142 includes a metrology device 118 to provide a process feed-back for real-time control of the polishing fluid distribution. You may. Generally, metrological device 118 detects a polishing metric such as polishing time, thickness of the surface film being polished on the substrate, surface shape or other substrate characteristics.

In one embodiment, the polishing material 108 may include a window 160 that allows the metrological device 118 to inspect the surface of the substrate 112 disposed opposite the polishing material 108. Metrological device 118 generally includes a sensor 162 that emits a beam 164 that passes through window 160 to substrate 112. The first portion of the beam 164 is reflected by the surface of the substrate 112 and the second portion of the beam 164 is reflected by a layer of material underlying the polished surface of the substrate 112. The reflected beam is received by the sensor 162 and the wavelength difference between the two portions of the reflected beam is analyzed to determine the material thickness on the surface of the substrate 112. In general, thickness information is provided to a controller (not shown) that regulates the polishing fluid distribution on the polishing material 108 to produce the desired polishing result on the surface of the substrate. Monitoring systems that may be used to advantage are disclosed in US patent application Ser. No. 08 / 689,930, filed on August 16, 1996, incorporated herein by Viral et al.

Optionally, metrological device 118 may include additional sensors to monitor polishing parameters across the width of substrate 112. The additional sensor allows the distribution of polishing fluid 114 to be adjusted across the width of the substrate 112 so that more or less material is removed at one portion relative to another portion of the substrate 112. Additionally, the flow rate adjustment process from nozzles 140 and 142 may occur during the polishing process to dynamically control the material removal rate across the substrate 112 at literally a predetermined time. For example, the center of the substrate 112 is polished more quickly by providing more polishing fluid to the center of the substrate 112 at the beginning of the polishing process and the periphery of the substrate 112 is more polished at the end of the polishing process. It may be polished more quickly by providing the fluid to the surrounding area.

3 illustrates another embodiment of a polishing fluid delivery system 300 having multiple nozzles 302. System 300 is configured similarly to fluid delivery system 102 of FIG. 1 (ie, has a single polishing fluid delivery line) or a dedicated supply line 304 in which each nozzle 302 is coupled to fluid source 306. It may be configured to have). A metering device 308 is fluidly coupled to each supply line 304. The metering device 308 may be a metering pump, such as a gear pump, a peristaltic pump, a positive displacement pump, a diaphragm pump, or the like. Each metering device 308 is coupled to a controller (not shown) that controls the amount of polishing fluid 114 provided to each nozzle 302 of the system 300. Because each metering device 308 is independently controllable, the flow of polishing fluid 114 from each of the plurality of nozzles 302 is regulated independently of the other nozzles so that the polishing fluid 114 on the polishing material 108 is controlled. The distribution of can be arranged in a substantially infinite configuration.

As noted above, each metering device may vary the polishing flow delivered to the polishing material 108 over the polishing process. For example, one of the nozzles 302 may increase the flow of polishing fluid 114 flowing through the nozzle while the substrate is polished. Another one of the nozzles may reduce the flow of polishing fluid 114 during polishing. Of course, an infinite change in nozzle flow rate at any given time may be configured to produce the desired polishing result. Since the flow of polishing fluid is independently controllable through each nozzle 302, the polishing properties may be adjusted across the width of the substrate over the substrate processing period.

Fluid delivery source 306 may be used in conjunction with metrological device 308 to control the rate or location of material removal from the surface 318 of the substrate 112 being polished. In general, the residual thickness or removal rate of the material on the surface 318 of the substrate 112 may be detected by the metrological device 308 and the desired polishing results, eg alternately around the substrate 112 A controller is provided that adjusts the various flow rates exiting each nozzle 302 to form faster polishing.

In one embodiment, the polishing material 108 may include a window 310 that allows the metrological device 308 to inspect the surface 318 of the substrate 112 disposed opposite the polishing material 108. . Metrological device 308 generally includes a sensor 314 that emits a beam 316 that passes through the window 310 to the substrate 112. The first portion of the beam 316 is reflected by the surface 318 of the substrate 108 and the second portion of the beam 316 is below the polished surface 318 of the substrate 108. Is reflected by. The reflected beam is received by the sensor 314 and the wavelength difference between the two portions of the reflected beam is analyzed to determine the material thickness on the surface 318 of the substrate 112. Generally, thickness information is provided to a controller that regulates the polishing fluid distribution on the polishing material 108 to produce the desired polishing result on the surface 318 of the substrate.

Optionally, metrological device 308 may include additional sensors to monitor polishing parameters across the width of substrate 112. The additional sensor allows the distribution of polishing fluid 114 to be adjusted across the width of the substrate 112 so that more or less material is removed at one portion relative to another portion of the substrate 112. Additionally, the flow rate adjustment process from the nozzle 302 may occur during the polishing process, which dynamically controls the material removal rate across the substrate 112 at a predetermined time. For example, the center of the substrate 112 is polished more quickly by providing more polishing fluid to the center of the substrate 112 at the beginning of the polishing process and the periphery of the substrate 112 is more polished at the end of the polishing process. It may be polished more quickly by providing the fluid to the surrounding area.

5 illustrates another embodiment of a polishing fluid delivery system 500. System 500 includes an arm 502 configured to position a plurality of polishing fluid delivery tubes 506 on the polishing surface 570. Arm 502 is configured to selectively provide a polishing fluid to different portions of polishing surface 570, thereby controlling the distribution of the polishing fluid across the width (or diameter) of polishing surface 570, resulting in polishing rate. . In one embodiment, the distribution of polishing fluid across the polishing surface 570 may be controlled by positioning the tube 506 to allow the polishing fluid to flow to a predetermined position. In another embodiment, the flow through the tube 506 may be selectively turned on or off.

In the embodiment shown in FIG. 5, the arm 502 has a hole 504 in which a plurality of polishing fluid delivery tube receivers, for example, the tube 506, are selectively positioned. In general, arm 502 has a greater number of holes 504 than tube 506 so that individual tubes 506 are selectively positioned along arm 502. Since the position of the tube 506 along the arm 502 indicates that a portion of the polishing surface 570 receives the polishing fluid during polishing, the choice of the hole 504 used to position the tube 506 is Controlling the distribution of the polishing fluid on the polishing surface 570 allows control of the local polishing rate across the width of the substrate 574 (shown in phantom). It is contemplated that the position of the tube 506 may be fixed and adjusted along the arm 502 by other devices or methods, such as clamps, sliders, straps and slots.

Arm 502 generally includes opposing second side 510 and first side 508 oriented perpendicular to polishing surface 570. The distal end 512 joins both sides 508 and 510. The polishing fluid delivery tube containing the hole 504 is disposed along at least one of the sides 508, 510. Arm 502 may include a bend along its length to provide clearance to polishing head 572 that holds substrate 574 (shown in phantom) relative to polishing surface 570 during processing. It may be.

In the embodiment shown in FIG. 5, holes 504 are arranged along both sides 508, 510 and end 512 of arm 500. The first set 514 of holes 504 is disposed along the first side 508, the second set 516 of holes 504 is disposed along the second side 510, and the hole 504 Third set 518 is disposed along end 512. The number and position of the holes 508 may be varied such that the position of the tube 506 is allowed at predetermined intervals to provide some polishing uniformity during polishing. For example, the first set 514 includes nine holes 504 spaced 0.5 inches apart, the second set 516 includes 10 holes 504 spaced 0.5 inches apart, The third set 518 may include two holes 504. Therefore, the position of the tube 506 along the arm 502 may be selected to allow the polishing fluid to flow to a separate portion of the polishing surface to control the local polishing rate across the width of the substrate.

In the embodiment shown in FIG. 5, the tube 506 may be located within a group of tubes 504 to form the desired polishing uniformity on the substrate 574. The first tube 506A is located in one of the first sets 514 of holes 504 such that the polishing fluid flows through the first portion 562 of the polishing surface 570. The second tube 506B is located in the other one of the first sets 514 of holes 504 such that the polishing fluid flows through the second portion 564 of the polishing surface 570. The third tube 506C is located in one of the second sets 516 of holes 504 such that the polishing fluid flows through the third portion 566 of the polishing surface 570. The fourth tube 506D is located in one of the third sets 518 of holes 504 such that the polishing fluid flows through the first portion 562 of the polishing surface 570. By moving any one of the tubes 506A-D to another hole 504, the distribution of polishing fluid on the polishing surface 570 is altered and thus the material removal rate across the diameter of the substrate 574. will be. The position of the tubes 506A-D can be used to produce certain polishing results (i.e., in-situ) while polishing a single substrate, to improve system flexibility when polishing different materials, and It may be moved along arm 502 to provide greater process control flexibility in tuning to produce a desired polishing uniformity or polished profile of the substrate. For example, the tubes 506A-D may be formed of the first group in response to a change in substrate surface properties, such as from oxide polishing to copper polishing, a change in surface profile between incoming substrates, or a change in microstructure width. It may be repositioned from the hole 504 to the hole 504 of the second group.

Optionally, the distribution of the polishing fluid on the polishing surface 570 may be altered by continuously flowing the polishing fluid along the tube 506. For example, the polishing fluid may be applied to the tube during the first portion of the polishing process to polish the substrate 5546 to a desired polishing rate profile across the diameter of the substrate (ie, the polishing rate is different across the diameter of the substrate). May be provided via 506A-D. In the second portion of the polishing process, flow through the fourth tube 506D is provided to change the distribution of polishing fluid on the polishing surface 570 to change the polishing rate profile. Flow through the tubes 506A-D may be turned on and off in various combinations to form the corresponding polishing performance. The flow process through the tubes 506A-D may be controlled in response to a sensed polishing metric as described above. Optionally, the flow process through the tubes 506A-D may be selected to form a uniform polishing of the substrate by compensating for changes in other process characteristics or variables that affect local polishing rates.

Referring to FIG. 6, the arm 502 is generally supported by a post 602 that facilitates rotation of the arm 502 on the polishing surface 570. Arm 502 is oriented perpendicular to post 602 and in one embodiment is offset or bent along its length. Post 602 additionally provides a conduit to direct tube 506 to arm 502.

Each hole 504 formed in the arm 502 generally includes an upper threaded portion 608 and a lower portion 604. The lower portion 604 has a diameter smaller than the diameter of the upper portion 606, forming a step 608 in the hole 506. The bottom 604 is generally configured to allow the tube 506 to penetrate generously. Top 606 includes threaded portion 612. Each tube 506 is held in one of the holes 504 by the collet 610.

Referring again to FIG. 5, the collet 610 has a threaded outer portion 502 and has a generally tapering cylinder. The collet 610 is tapered from the central ring 506 to the narrow end 504. The narrow end 504 of the collet 610 includes a number of slots 508 that define a finger 510 extending from the central ring 506. Ring 506 is configured to fit snugly on tube 506. After the tube 506 is inserted into the hole 504 to a predetermined depth, the collet 610 is engaged with the threaded portion 612 of the hole 504. The tapered shaped collet 610 causes the finger 510 to press inwardly against the tube 506 when the collet 610 is screwed into the top 606 of the hole 504, thereby closing the tube 506. Clamp in 504.

Collet 610 allows tube 506 to extend a predetermined length below arm 502. Therefore, the outlet 614 of the tube 506 is firmly located close to the polishing surface and the arm 502 may be deposited at a greater distance from the polishing surface and on the arm 502 and subsequently contaminate the substrate during polishing and Keep away from contaminants and other debris that may be damaging. In one embodiment, the outlet 614 of the tube 506 extends at least 1 inch below the arm 502.

6 and 8 illustrate one embodiment of a plug 620 used to prevent polishing fluid and other contaminants from entering the hole 504 not occupied by a given tube 506. The plug 620 generally includes a cylindrical body 622 having concentric posts 624 extending from the first end 628 and threaded holes 630 formed concentrically in the second end 632. The post 624 is configured to fill the bottom 604 of the hole 504 generously to prevent polishing fluid and other contaminants from entering the hole 504. Posts 624 generally protrude slightly from the lower portion 644 of the arm 502 extending coplanar or facing the polishing surface 570. The set screw 626 is screwed into the top 606 of the hole 506 and presses the plug 620 against the staircase 608 to secure the plug 620 in the hole 504. Plug 620 may be removed from hole 504 by removing set screw 626 and inserting a threaded object (not shown) into threaded hole 630 of plug 620. Plug 620 may then be pulled out of hole 504.

Referring again to FIG. 6, arm 500 may include an optional spray system 640. Spray system 640 generally includes a tube 642 coupled to a lower portion 644 of arm 500. Tube 642 includes a plurality of nozzles 646 formed or coupled within tube 642 at spaced intervals. Tube 642 is coupled to cleaning fluid source 648 by routed conduit 650 via post 602. The cleaning fluid source 648 generally provides pressurized cleaning fluid, such as deionized water, through the nozzle 646 to the polishing surface 570 to remove contaminants or other debris from the polishing surface. One spray system that may be advantageously constructed from the present invention is disclosed in US Pat. No. 6,139,406, incorporated herein by reference and issued October 31, 2000 to Kennedy.

9 illustrates a cross-sectional view of another embodiment of a polishing fluid delivery system 900. The apparatus 900 has an arm 902 having a first side 904, an opposing second side 906 and a lower side 908 facing the polishing surface 910 and disposed between the sides 904, 906. ). Sides 904 and 906 generally define the length of arm 902 and a portion of the arm is configured to extend onto polishing surface 910.

Manifold 912 coupled to a polishing fluid source (not shown) extends along the length of arm 902. Manifold 912 is coupled to arm 902 and may be disposed within or integrally formed with arm 902. Manifold 912 generally includes a plurality of outlets 914 disposed in spaced relation along the length of manifold 912. The outlet 914 is configured to flow the polishing fluid from the manifold 912 to a separate portion of the polishing surface 910.

Each outlet 914 includes a flow control mechanism 916 coupled to the outlet. Flow control mechanism 916 may be a manual or automatic flow control device such as a pinch valve, proportional valve, needle valve, shutoff valve, metering pump, mass flow controller, and the like. Flow control mechanism 916 allows selectively turning on or off the flow from each outlet 914 to control the distribution of polishing fluid across the width of the polishing surface 910.

In one embodiment, the flow control mechanism 914, for example a solenoid valve, is coupled to the controller 918. Controller 918 allows each control mechanism 914 to be opened or closed in a predetermined process to facilitate adjustment of the material removal rate across the diameter of the substrate being polished. By using the controller 918 the velocity profile is adjusted in-situ. For example, the controller 918 may use a metrological device as shown in FIG. 1 to change the polishing profile in response to polishing metering such as polishing time, thickness of the surface film polished on the substrate, substrate shape or other substrate characteristics. 118).

Spray system 920 may also be coupled to arm 902 and configured to spray cleaning fluid onto polishing surface 920. Spray system 920 is generally similar to spray system 600 described with reference to FIG. 6.

Therefore, the polishing fluid delivery system allows to control the distribution of the polishing fluid to various portions of the polishing surface to adjust the material removal rate across the width of the substrate during polishing. Dispensing of the polishing fluid controls the relative amount of polishing fluid delivered from different locations along the arm, changes the position of the polishing fluid delivery tube along an arm extending on the polishing surface, or in one area of the substrate relative to another area. It may be controlled by selectively turning on and off the flow from the tube for faster polishing. Despite forming more flexible process windows, the distribution control of the polishing fluid advantageously reduces the amount of polishing fluid consumed during polishing, thereby reducing processing costs.

While the disclosure of the present invention has been shown and described in detail, those skilled in the art can readily devise various modifications that are incorporated into the disclosure and do not depart from the scope and spirit of the invention.

Claims (25)

A system for delivering a polishing fluid to a chemical mechanical polishing surface, An arm having a delivery portion at least partially disposed on the polishing surface, A first nozzle disposed on the delivery portion and configured to flow the polishing fluid at a first speed, and One or more second nozzles disposed on the delivery portion and configured to flow the polishing fluid at a second speed different from the first speed, A system for delivering a polishing fluid. The method of claim 1, At least one of the first nozzle or the second nozzle further comprises a flow control device coupled to the nozzles, A system for delivering a polishing fluid. The method of claim 2, The flow control device is a flow controller selected from the group consisting of an orifice, a needle valve, a proportional valve, a pinch valve, a restrictor, a mass flow controller and a metering pump, A system for delivering a polishing fluid. The method of claim 1, The arm further comprises a polishing fluid delivery line coupled to both the first and second nozzles, A system for delivering a polishing fluid. The method of claim 1, Further comprising a first fluid source coupled to the first nozzle and a second fluid source coupled to the second nozzle, A system for delivering a polishing fluid. The method of claim 1, Further comprising a plurality of nozzles configured to flow the polishing fluid at a controlled rate, wherein each nozzle is independently controllable, A system for delivering a polishing fluid. The method of claim 1, Further comprising a rotating platen configured to support a polishing material, the polishing material comprising the polishing surface, A system for delivering a polishing fluid. The method of claim 1, Wherein the first nozzle is located inside the second nozzle radially relative to the center of rotation of the polishing material, the first flow is 1.15 times or more than the second flow, A system for delivering a polishing fluid. The method of claim 1, The first flow is about 1.2 to about 20 times the second flow rate, A system for delivering a polishing fluid. The method of claim 1, Further comprising a metrological device configured to provide information used to control at least one flow through the nozzles, A system for delivering a polishing fluid. A system for delivering a polishing fluid to a chemical mechanical polishing surface, A platen supporting the polishing surface, A polishing head disposed on the platen, An arm having a delivery portion at least partially disposed on the polishing surface, A first nozzle disposed on the delivery portion and configured to flow the polishing fluid at a first controllable speed, At least one second nozzle disposed on the delivery unit and configured to flow the polishing fluid at a second controllable speed that is different from the first controllable speed, and A metrological device configured to provide information used to control at least one flow through the nozzles, A system for delivering a polishing fluid. A system for delivering a polishing fluid to a chemical mechanical polishing surface, An arm having a lower portion configured to face the polishing surface and a plurality of tube receivers, and At least one tube positioned between two or more of the tube receivers and coupled to the arm and configured to flow a polishing fluid; A system for delivering a polishing fluid. The method of claim 12, Two or more of the tube receivers define a first set of tube retaining holes spaced along the first side of the arm, Two or more different tube receivers spaced at equal distances from the second side of the arm disposed opposite the first side to define a second set of tube retention holes formed in the arm, A system for delivering a polishing fluid. The method of claim 12, Further comprising a collet for coupling the tube to the arm and penetrating the tube and disposed in each tube receiver, A system for delivering a polishing fluid. The method of claim 12, Further comprising one or more plugs disposed in the holes not occupied by the tube, A system for delivering a polishing fluid. The method of claim 15, The plug, A central body, and A post extending from said central body and protruding beyond said arm or at least coplanarly disposed, Each hole, A first part with a threaded section, A second portion disposed coaxially with the first portion and having a diameter smaller than the diameter of the first portion, A staircase formed at the boundary between the first and second portions, and A set screw coupled to the threaded section and for urging the central body of the plug against the staircase, The post of the plug fills the second part, A system for delivering a polishing fluid. The method of claim 12, Means for selectively changing the combination of tubes through which the polishing fluid passes; A system for delivering a polishing fluid. A system for delivering a polishing fluid to a chemical mechanical polishing surface, Arm, Multiple polishing fluid transfer tubes, A plurality of holes formed in the arm to receive the polishing fluid delivery tube, Each tube is disposed through one of the holes and coupled to the arm, The relationship between the polishing fluid delivery tube and the hole is expressed as A / B > 1, where A is the number of holes and B is the number of polishing fluid delivery tubes, A system for delivering a polishing fluid. A method of supplying a polishing fluid to a chemical mechanical polishing surface, Flowing the polishing fluid onto the pad at a first position at a first velocity, and Flowing the polishing fluid onto the pad at a second position at a second speed different from the first speed, A method of supplying a polishing fluid. The method of claim 19, The first speed is independently controllable with respect to the second speed, A method of supplying a polishing fluid. The method of claim 19, Flowing the polishing fluid at a first velocity, Adjusting the flow rate in response to polishing metering during polishing, A method of supplying a polishing fluid. A method of delivering a polishing fluid to a polishing surface of a chemical mechanical polisher, Providing a polishing fluid delivery arm having a plurality of tube holding positions, the plurality of tube holding positions exceeding a number of polishing fluid delivery tubes coupled to the arm, Providing a polishing fluid delivery arm, and Selecting a relative space between the at least first and second polishing fluid delivery tubes along the arm from the plurality of tube retention positions to form a desired polishing result, A method of delivering a polishing fluid. The method of claim 22, At least one of the polishing fluid tubes is moved to a different position along the arm in response to a change in the surface properties of the substrate being polished A method of delivering a polishing fluid. The method of claim 22, At least one of the polishing fluid tubes is moved to a different position along the arm to change the local polishing rate across the diameter of the substrate, A method of delivering a polishing fluid. A method of delivering a polishing fluid to a polishing surface of a chemical mechanical polisher, Flowing a polishing fluid into a manifold coupled to a plurality of outlets disposed in a spaced apart relationship on the polishing surface, Flowing a polishing fluid through at least one of the outlets, and Preventing the polishing fluid from flowing through one or more of the outlets, One or more outlets having a condition characterized by the flow or nonflow of the polishing fluid are changed in in situ to opposite conditions, A method of delivering a polishing fluid.